| Blackstairs Mountain | |
| Other Name: | An Staighre Dubh |
| Elevation M: | 735 |
| Listing: | Marilyn |
| Language: | Irish |
| Location: | County Carlow, County Wexford, Ireland |
| Range: | Blackstairs Mountains |
| Map: | island of Ireland |
| Map Relief: | yes |
| Coordinates: | 52.5497°N -6.8062°W |
| Grid Ref Ireland: | S810448 |
| Topo: | OSi Discovery 68 |
Blackstairs Mountain is the second-highest mountain in the Blackstairs Mountains of southern Leinster in the Republic of Ireland. The mountain stretches from Rathgeran to Gowlin at Cathaoirs Den.